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Re: Winonaites in brief

I have decided to get to the nitty gritty here. Below is just brief one 
liners(no pun intended) on the various aspects of winonaites. I think 
that it may be best to only put a summary up here, as lengthy 
explanation here may only confuse people with this limited medium.

-Winonaites are primitive achondrites.

-They are derived from a precursor chondritic material that is unlike  
any previously known, meaning that mineral composition are between     H 
and E chondrites, and the oxygen isotope composition is    different 
from anything known(I wish I could provide more on this,     but I am 
limited to published data, sorry). 

-They have undergone extensive heating and metamorphism, which all but 
 obliterated the chondritic signature.

-Ages range from 4.4 billion-4.53 billion years old.

-They resemble IAB iron meteorite silicate inclusions in composition,
 mineralogically, and in texture.

-Impact(s) have mixed different lithologies into their matrix while    
cooling was in progress. 

-Members of this group are:Winona,Mount Morris(Wisconsin),Tierra 
 Blanca, Pontlyfni, Y-74025, Y-75300, Y-8005, QUE 94535, and possibly 
 Y-75305, and Y-75261.

That is the short and brief of it. I hope this helps out those who were 
looking for information on these unique meteorites

Reference: A petrologic and isotopic study of winonaites:Evidence for            
early partial melting, brecciation, and metamorphism.
           Benedix G.K. and others (1998) Geochimica et Cosmochimica
           Acta, Vol.62, no 14, pp.2535-2553

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